Mounting means for light sources



Aug. 13, 1940. O J. MOEHLER 2,211,605

MOUNTING MEANS FOR LIGHT SOURCES Filed Sept. 8, 1958 Flg.

INVENTOR Ob'bo J. Moehle r BY Patented Aug. 13,1940

UNETED STATES (Otto J.

Moehler, Bloomfield, N. 3., assignor, by

mesne assignments, to General Electric Gompany, a corporation of New York.

Application September 8, 1938, Serial No. 229,0ii

3 Claims.

The present invention relates to mounting means for tubular light sources.

A particular object of the invention is to provide a novel supporting means for a tubular light 5 source which can be readily assembled and which will be relatively inexpensive. Another object of my invention is to provide a novel connecting and mounting means which will withstand high temperatures. A further object of the invention is to provide a supporting means which will safeguard the user from accidental contacts with the electrical connections. Still other objects and advantages of the invention will appear from the following detailed specification, or from an inspection of the accompanying drawing.

The invention consists in the new and novel combination of elements hereinafter set forth and claimed.

Certain types of tubular light sources, such as the quartz burners used for ultraviolet irradiation, have graded seals protruding from the ends thereof which are protected by metal sleeves attached to the tubular envelopes. These sleeves ordinarily are permanently connected to the inleads, and thus serve as the electrical terminals of the device, through which contact is made to the electrical circuit. Due to the high wattage input which is usual with these devices these sleeves commonly operate at a relatively high temperature, often approaching red heat in operation. This high temperature creates a real problem in the connection of these devices to external circuits, especially where snap-in type connections are desired due to their obvious convenience, for

the springs ordinarily relied upon to provide good electrical contact rapidly lose their resilience under these conditions, producing contact resistance which is aggravated by the oxide film which develops. The relatively high voltages employed in these devices, especially in sizes designed for a thousand watts and more, has also created a hazard against which the user must be protected during the insertion or removal of a device from the circuit.

I have now discovered that both of these difllculties are entirely eliminated by a novel mounting and connecting means of my invention. According to my invention the metal sleeveof these devices is firmly attached to a metal member 0 which forms the male connection of a separable plug, this member being of suflicient length to prevent undue heat conduction to the springs forming the female connection into which it is inserted. This metal member in the preferred structure is enclosed, together with the metal sleeve on the light source, within an insulating housing whereby accidental contact with any of the live metal parts is precluded. As a further feature of my invention this housing, the light source and the male connecting member are so interlocked that a single screw semi-permanently combines them into a single operating unit which may be plugged into the female receptacle and removed therefrom at will.

For the purpose of illustrating my invention I W have shown a preferred embodiment thereof in the accompanying drawing, in which:

Fig. 1 is an elevational view in part section, of a tubular light source having my novel mounting means connected thereto, and m Fig. 2 is a sectional view, showing the lamp as it would appear at the section Z-'-2 of Fig. l plugged into a female connecting member, with which it interlocks to prevent accidental contact with the metal members. 29

As shown in this drawing the light source I is a tubular type quartz lamp having a metal sleeve 2 preferably of nickel, affixed to each end thereof in the manner disclosed in Buttolph Patent 2,056,157, issued October 6, 1936. As here shown this lamp is of the type having two activated thermionic cathodes and containing a fixed gas such as argon and a limited quantity of mercury which is intended to be wholly vaporized in operation, but it is to be understood that the usefulness of the invention is not limited to this particular type of lamp. The inleads to this lamp extend through graded seals (not shown) within the sleeves 2, whereby these seals are protected from mechanical injury, and are electrically connected in a Well known manner to said sleeves. The central portion of said sleeves is made smaller in diameter than the ends thereof, and about this constriction 3 there is placed a metal strap 4 of brass or the like. This strap is preferably performed to fit the curvature of the construction 3, and is narrowed (not shown) near the center of the curved portion thereof to facilitate the bending of the strap into contact with the constricted portion of the sleeve 2 after it has been placed in registry therewith without deforming the remainder of the preformed portion. With the strap 4 thus in position in the constriction 3 the sleeve 2 is then slid into the recess 5 in the porcelain body 6. This recess has a length equal to, or 5 slightly greater than, that of the sleeve 2, and is of slightly larger diameter than said sleeve, the intervening space being filled with asbestos twine I or other suitable compressible material, and an opening is preferably provided in the end of said recess for ventilating purposes. On one side of the porcelain body 6 there is a boss 8 which has a slot 8 therein opening into the recess 5, through which the strap 4 can pass as the sleeve 2 is slid into position within said recess. When the sleeve 2 is thus positioned entirely within the recess 5 one end of the strap 4 extends from the slot 9 just enough to be gripped and held against the other end thereof during the insertion, while the other end extends to form the male connection, the end thereof preferably being bent at an angle, as shown at H). With the parts thus positioned a clamping screw H is inserted through a slot 12 in the boss 8 which extends transversely to the slot 8 and into suitable openings in the strap 4, one of which is conveniently threaded. This screw tightens the strap 4 onto the constriction 3, whereby good electrical contact is made with the sleeve 2, and at the same time locks the assembly in place within the insulating body 6, due to the fact that it is too long to pass through the slot 9. Hence as thus assembled the sleeve 2 with its attached lamp 1 cannot be removed from the insulating body 6, and all metal parts with the single exception of the strap 4, are protected against accidental contact therewith. In this connection it may be noted that the outwardly turned rim l3 on the insulating body 6 is designed to keep the fingers well away from the end of the sleeve 2.

By making the length of the constrictions 3 somewhat greater than the width of the contact strap 4 provision is made for mounting the two straps 4 at a predetermined distance from each other, irrespective of slight variations in the length of the lamp 4, such as are expected with a material which is as difiicultly workable as quartz.

This novel assembly of lamp and attached mounting and connecting means is adapted to be plugged into a pair of cooperating female sockets as shown in Fig. 2. Each of these sockets comprises a porcelain body l4 having a skirt l5 at the end thereof which encloses a portion of the boss 8. The connecting strap 4 extends into a suitable recess in said body and into contact with the ends of the spring member l6. Said ends are each bent outwardly from the plane of the axis to substantially the same angle as the tip ID of the strip 4, and said strip is of such length that when the two parts of the connector are in position said tip It] lies against the correspondingly bent portion of one end of the spring contact 15. Thus the strip 4 cannot be removed from this socket without bending the ends of the contact spring apart, and the lamp is thus resiliently held in place even though the structure be inverted from the position shown. A screw I! which holds the contact spring I6 in position passes through a suitable opening in the end of the porcelain body I4 and provides convenient means to connect the lamp I to the external circuit.

With this novel structure the amount of heat which is conducted by the contact strip 4 to the contact spring I6 is not suiiicient to impair the functioning of the latter in any way. Every live part of the electrical circuit is likewise fully protected against accidental contact therewith, while at the same time adequate openings are provided for the flow of cooling air currents.

While I have described my invention by reference to a particular embodiment thereof, it is to be understood that various omissions, substitutions and changes, within the scope of the appended claims, may be made therein without departing from the spirit of the invention.

I claim as my invention:

1. In combination, a, tubular light source having a metal sleeve attached thereto at one end, said sleeve being electrically connected to a terminal of said source, a conducting strap clamped about said sleeve, said strap having a rigid extension adapted to serve as a male connector and an insulating body about said sleeve and said strap, said body being perforated to permit the cooling of said sleeve and said strap by the ambient atmosphere.

2. In combination, a tubular light source having two electrical terminals, a metal sleeve attached to each end of said source, each of said sleeves being electrically connected to one of said terminals, a conducting strap about each of said sleeves with one end thereof extending to form a male connector, means to clamp said strap to said sleeve and an insulating body about said sleeve and said strap, said body being locked in place by the clamping means for said strap.

3. In combination, a tubular light source having two electrical terminals, a metal sleeve attached to each end of said source, each of said sleeves being electrically connected to one of said terminals, a conducting strap about each of said sleeves with one end thereof extending to form a male connector, means to clamp said strap to said sleeve and an insulating body about said sleeve and said strap, said body being locked in place by the clamping means for said strap and being perforated to permit the cooling of said sleeve and said strap by the ambient atmosphere.

O'ITO J. MOEHLER. 

